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The Relationship between Fractures and Tectonic Stress Field in the Extra Low-Permeability Sandstone Reservoir at the South of Western Sichuan Depression 被引量:13
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作者 曾联波 漆家福 李跃纲 《Journal of China University of Geosciences》 SCIE CSCD 2007年第3期223-231,共9页
The formation and distribution of fractures are controlled by paleotectonic stress field, and their preservative status and effects on development are dominated by the modern stress field. Since Triassic, it has exper... The formation and distribution of fractures are controlled by paleotectonic stress field, and their preservative status and effects on development are dominated by the modern stress field. Since Triassic, it has experienced four tectonic movements and developed four sets of tectonic fractures in the extra low-permeability sandstone reservoir at the south of western Sichuan depression. The strikes of fractures are in the S-N, NE-SW, E-W, and NW-SE directions respectively. At the end of Triassic, under the horizontal compression tectonic stress field, for which the maximum principal stress direction was NW.SE, the fractures were well developed near the S-N faults and at the end of NE-SW faults, because of their stress concentration. At the end of Cretaceous, in the horizontal compression stress fields of the NE-SW direction, the stress was obviously lower near the NE-SW faults, thus, fractures mainly developed near the S-N faults. At the end of Neogene-Early Pleistocene, under the horizontal compression tectonic stress fields of E-W direction, stress concentrated near the NE-SW faults and fractures developed at these places, especially at the end of the NE-SE faults, the cross positions of NE-SW, and S-N faults. Therefore, fractures developed mostly near S-N faults and NE-SW faults. At the cross positions of the above two sets of faults, the degree of development of the fractures was the highest. Under the modern stress field of the NW-SE direction, the NW-SE fractures were mainly the seepage ones with tensional state, the best connectivity, the widest aperture, the highest permeability, and the minimum opening pressure. 展开更多
关键词 fracture tectonic stress field extra low-permeability reservoir south of western Sichuan depression
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Adaptive Fuzzy Torque Control of Passive Torque Servo Systems Based on Small Gain Theorem and Input-to-state Stability 被引量:11
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作者 WANG Xingjian WANG Shaoping ZHAO Pan 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2012年第6期906-916,共11页
Passive torque servo system (PTSS) simulates aerodynamic load and exerts the load on actuation system, but PTSS endures position coupling disturbance from active motion of actuation system, and this inherent disturb... Passive torque servo system (PTSS) simulates aerodynamic load and exerts the load on actuation system, but PTSS endures position coupling disturbance from active motion of actuation system, and this inherent disturbance is called extra torque. The most important issue for PTSS controller design is how to eliminate the influence of extra torque. Using backstepping technique, adaptive fuzzy torque control (AFTC) algorithm is proposed for PTSS in this paper, which reflects the essential characteristics of PTSS and guarantees transient tracking performance as well as final tracking accuracy. Takagi-Sugeno (T-S) fuzzy logic system is utilized to compensate parametric uncertainties and unstructured uncertainties. The output velocity of actuator identified model is introduced into AFTC aiming to eliminate extra torque. The closed-loop stability is studied using small gain theorem and the control system is proved to be semiglobally uniformly ultimately bounded. The proposed AFTC algorithm is applied to an electric load simulator (ELS), and the comparative experimental results indicate that AFTC controller is effective for PTSS. 展开更多
关键词 flight simulation adaptive control fuzzy control passive torque servo system electric load simulator extra torque small gain theorem input-to-state stability
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On Restricted Connectivity and Extra Connectivity of Hypercubes and Folded Hypercubes 被引量:12
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作者 徐俊明 朱强 +1 位作者 侯新民 周涛 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第2期203-207,共5页
Given a graph G and a non-negative integer h, the h-restricted connectivity κh(G) of G is the minimum cardinality of a set of vertices of G, in which at least h neighbors of any vertex is not included, if any, whos... Given a graph G and a non-negative integer h, the h-restricted connectivity κh(G) of G is the minimum cardinality of a set of vertices of G, in which at least h neighbors of any vertex is not included, if any, whose deletion disconnects G and every remaining component has the minimum degree of vertex at least h; and the h-extra connectivity κh(G) of G is the minimum cardinality of a set of vertices of G, if any, whose deletion disconnects G and every remaining component has order more than h. This paper shows that for the hypercube Qn and the folded hypercube FQn, κ1(Qn)=κ(1)(Qn)=2n-2 for n≥3, κ2(Qn)=3n-5 for n≥4, κ1(FQn)=κ(1)(FQn)=2n for n≥4 and κ(2)(FQn)=4n-4 for n≥8. 展开更多
关键词 CONNECTIVITY conditional connectivity restricted connectivity extra connectivity HYPERCUBE folded hypercube
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Impact coefficient and reliability of mid-span continuous beam bridge under action of extra heavy vehicle with low speed 被引量:11
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作者 刘波 王有志 +1 位作者 胡朋 袁泉 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1510-1520,共11页
To analyze the dynamic response and reliability of a continuous beam bridge under the action of an extra heavy vehicle, a vehicle–bridge coupled vibration model was established based on the virtual work principle and... To analyze the dynamic response and reliability of a continuous beam bridge under the action of an extra heavy vehicle, a vehicle–bridge coupled vibration model was established based on the virtual work principle and vehicle–bridge displacement compatibility equation, which can accurately simulate the dynamic characteristics of the vehicle and bridge. Results show that deck roughness has an important function in the effect of the vehicle on the bridge. When an extra heavy vehicle passes through the continuous beam bridge at a low speed of 5 km/h, the impact coefficient reaches a high value, which should not be disregarded in bridge safety assessments. Considering that no specific law exists between the impact coefficient and vehicle speed, vehicle speed should not be unduly limited and deck roughness repairing should be paid considerable attention. Deck roughness has a significant influence on the reliability index, which decreases as deck roughness increases. For the continuous beam bridge in this work, the reliability index of each control section is greater than the minimum reliability index. No reinforcement measures are required for over-sized transport. 展开更多
关键词 continuous beam bridge extra heavy vehicle coupled vibration impact coefficient reliability
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外源性的锌诱导兔肝金属硫蛋白对原代肝细胞铅毒性的保护作用 被引量:10
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作者 郝守进 田佩瑶 +1 位作者 唐庆平 茹炳根 《卫生研究》 CAS CSCD 北大核心 2002年第4期229-232,共4页
锌诱导兔肝金属硫蛋白 (Zn7-MT)是一种富含半胱氨酸的低分子量的锌结合蛋白 ,在金属代谢和解毒方面起着十分重要的作用。本项研究是采用外源性的MT在鼠原代肝细胞 (RPHC)中 ,对金属铅毒性方面所起的保护作用进行研究。其方法是将RPHC单... 锌诱导兔肝金属硫蛋白 (Zn7-MT)是一种富含半胱氨酸的低分子量的锌结合蛋白 ,在金属代谢和解毒方面起着十分重要的作用。本项研究是采用外源性的MT在鼠原代肝细胞 (RPHC)中 ,对金属铅毒性方面所起的保护作用进行研究。其方法是将RPHC单层培养 2 4小时 ,然后加入一定浓度的 (Zn7-MT)后 ,并将RPHC在各种浓度铅中 ,实施暴露 2 4小时 ,分别测定细胞乳酸脱氢酶的渗出量和K+的损失来评价它们对细胞的毒性作用。同时 ,研究铅在细胞内、外的铅元素的分布和吸收情况 ,以及在Zn7-MT的存在下 ,探讨Zn7-MT在RPHC中对铅毒性方面所起的作用。实验结果证明 ,在Zn7-MT的存在下 ,铅对细胞的毒性作用显著性降低 ,其细胞对铅元素的吸收和聚集产生一定的改变。在对照组细胞的胞质中 ,铅可能主要与高分子量的蛋白结合 ,而在Zn7-MT存在下 。 展开更多
关键词 外源性 锌金属硫蛋白 鼠肝原代细胞 保护作用
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硬膜下积液的形成分期和治疗 被引量:8
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作者 陶志强 刘伟国 《浙江创伤外科》 2005年第5期413-415,共3页
关键词 硬膜下积液 FLUID 治疗 分期 英文文献 积液性质 extra 红细胞 高蛋白
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AKT and ERK1/2 signaling in intrahepatic cholangiocarcinoma 被引量:9
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作者 KJ Schmitz H Lang +4 位作者 J Wohlschlaeger GC Sotiropoulos H Reis KW Schmid HA Baba 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第48期6470-6477,共8页
Intrahepatic cholangiocarcinomas (ICC) are neoplasms that originate from cholangiocytes and can occur at any level of the biliary tree. Surgical resection is the current therapy of choice for this highly aggressive ca... Intrahepatic cholangiocarcinomas (ICC) are neoplasms that originate from cholangiocytes and can occur at any level of the biliary tree. Surgical resection is the current therapy of choice for this highly aggressive cancer. However, the 5-year survival still is poor, with high recurrence rates. Due to the intrahepatic growth a signifi cant proportion of patients present with advanced disease and are not candidates for curative surgery or transplantation. The existing palliative options are of limited benefit and there is a great necessity for novel therapeutic options. In this article we review the role of the phosphoinositide 3-kinase(PI3K)/ AKT and extracellular regulated kinase (ERK) signaling pathways in ICC and present new data on the prognostic value of these protein kinases. Finally, we discuss future upcoming therapeutic options based on targeting these signaling pathways. 展开更多
关键词 extra cellular regulated kinases CHOLANGIOCARCINOMA Prognosis ONCOLOGY IMMUNOHISTOCHEMISTRY
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Helicobacter pylori:Does it add to risk of coronary artery disease 被引量:8
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作者 Vishal Sharma Amitesh Aggarwal 《World Journal of Cardiology》 CAS 2015年第1期19-25,共7页
Helicobacter pylori(H. pylori) is a known pathogen implicated in genesis of gastritis, peptic ulcer disease, gastric carcinoma and gastric lymphoma. Beyond the stomach, the organism has also been implicated in the cau... Helicobacter pylori(H. pylori) is a known pathogen implicated in genesis of gastritis, peptic ulcer disease, gastric carcinoma and gastric lymphoma. Beyond the stomach, the organism has also been implicated in the causation of immune thrombocytopenia and iron deficiency anemia. Although an area of active clinical research, the role of this gram negative organism in causation of atherosclerosis and coronary artery disease(CAD) remains enigmatic. CAD is a multifactorial disease which results from the atherosclerosis involving coronaryarteries. The major risk factors include age, diabetes mellitus, smoking, hypertension and dyslipidemia. The risk of coronary artery disease is believed to increase with chronic inflammation. Various organisms like Chlamydia and Helicobacter have been suspected to have a role in genesis of atherosclerosis via causation of chronic inflammation. This paper focuses on available evidence to ascertain if the role of H. pylori in CAD causation has been proven beyond doubt and if eradication may reduce the risk of CAD or improve outcomes in these patients. 展开更多
关键词 extra gastric CORONARY artery disease HELICOBACTER PYLORI ATHEROSCLEROSIS Inflammation
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Mechanism and control technology of strong ground pressure behaviour induced by high-position hard roofs in extra-thick coal seam mining 被引量:8
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作者 Chao Pan Binwei Xia +2 位作者 Yujun Zuo Bin Yu Changnan Ou 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第3期499-511,共13页
This work aimed at revealing the mechanism of strong ground pressure behaviour(SGPB)induced by high-position hard roof(HHR).Based on the supporting structures model of HHR,a modified voussoir beam mechanical model for... This work aimed at revealing the mechanism of strong ground pressure behaviour(SGPB)induced by high-position hard roof(HHR).Based on the supporting structures model of HHR,a modified voussoir beam mechanical model for HHR was established by considering the gangue support coefficient,through which the modified expressions of limit breaking span and breaking energy of HHR were deduced.Combined with the relationship between the dynamic-static loading stress of supporting body(hydraulic support and coal wall)and its comprehensive supporting strength,the criteria of ground pressure behaviour(GPB)induced by HHR were discussed.The types of Ⅰ_(1),Ⅰ_(2),Ⅱ_(1),andⅡ_(2) of GPB were interpreted.Results showed that types Ⅰ_(1) and Ⅰ_(2) were the main forms of SGPB in extra-thick coal seam mining.The main manifestation of SGPB was static stress,which was mainly derived from the instability of HHR rather than fracture.Accordingly,an innovative control technology was proposed,which can weaken static load by vertical-well separated fracturing HHR.The research results have been successfully applied to the 8101 working face in Tashan coal mine,Shanxi Province,China.The results of a digital borehole camera observation and stress monitoring proved the rationality of the GPB criteria.The control technology was successful,paving the way for new possibilities to HHR control for safety mining. 展开更多
关键词 extra thick coal seam High-position hard roof Strong ground pressure behaviour Supporting structures Criteria of ground pressure behaviour Controlling effects
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Arch structure effect of the coal gangue flow of the fully mechanized caving in special thick coal seam and its impact on the loss of top coal 被引量:9
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作者 Zhang Ningbo Liu Changyou 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第4期593-599,共7页
Based on the characteristics of the top coal thickness of the fully mechanized caving in special thick coal seam,the long distance of coal gangue caving,as well as the different sizes of the coal gangue broken fragmen... Based on the characteristics of the top coal thickness of the fully mechanized caving in special thick coal seam,the long distance of coal gangue caving,as well as the different sizes of the coal gangue broken fragment dimension and spatial variation of drop flow,this paper uses laboratory dispersion simulation experiment and theoretical analysis to study the arch structure effect and its influence rule on the top coal loss in the process of coal gangue flow.Research shows that in the process of coal gangue flow,arch structure can be formed in three types:the lower arch structure,middle arch structure,and upper arch structure.Moreover,the arch structure has the characteristics of dynamic random arch,the formation probability of dynamic random arch with different layers is not the same,dynamic random arch caused the reduction of the top coal fluency;analyzing the dynamic random arch formation mechanism,influencing factors,and the conditions of instability;the formation probability of the lower arch structure is the highest,the whole coal arch and the coal gangue arch structure has the greatest impact on top coal loss.Therefore,to prevent or reduce the formation of lower whole coal arch structure,the lower coal gangue arch structure and the middle whole coal arch structure is the key to reduce the top coal loss.The research conclusion provides theoretical basis for the further improvement of the top coal recovery rate of the fully mechanized caving in extra thick coal seam. 展开更多
关键词 extra thick coal seam Coalgangue flow Top coalloss Dynamic random arch effect
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基于无人机高光谱影像的水稻叶片SPAD值反演方法研究 被引量:1
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作者 谢东 何敬 +3 位作者 何嘉晨 王彬 林远杨 刘刚 《山西农业大学学报(自然科学版)》 CAS 北大核心 2024年第1期120-129,共10页
[目的]通过无人机高光谱影像实现对水稻叶绿素含量高效、无损监测是现代化精准农业发展的重要手段。研究水稻叶片原始光谱的不同预处理方法及其组合,构建不同光谱参数进行模型反演,得到研究区水稻叶片SPAD值的最佳反演模型,可为高效无... [目的]通过无人机高光谱影像实现对水稻叶绿素含量高效、无损监测是现代化精准农业发展的重要手段。研究水稻叶片原始光谱的不同预处理方法及其组合,构建不同光谱参数进行模型反演,得到研究区水稻叶片SPAD值的最佳反演模型,可为高效无损监测水稻叶绿素含量提供参考。[方法]以四川省成都市青白江区姚渡镇水稻种植区的水稻为研究对象,分别测定其叶片SPAD值和500~900 nm范围内的高光谱反射率,对原始反射率进行一阶微分(D1)、Savitzky-Golay卷积平滑(SG平滑)、标准正态变换(SNV)和多元散射校正(MSC)及其组合的预处理方式,通过相关系数筛选出p<0.1的特征波段作为第1种光谱参数,在特征波段的基础上进行主成分分析(PCA)降维,将得到的主成分作为第2种光谱参数。将2种参数分别作为Extra Trees模型的输入变量,建立研究区水稻SPAD值的反演模型。[结果]相比于利用相关系数筛选的特征波段所建的模型,通过PCA对特征波段进行降维,得到的光谱参数建模精度更高,其中,ET_D1和ET_SG_MSC的R~2分别由0.769和0.782增加到0.793和0.825,提升幅度为3%和5.5%;ET_SG_SNV的R~2由0.754增加到0.796,提升幅度为5.6%;模型ET_PCA_特征_SG_MSC精度最高,R~2和RMSE分别为0.825和0.984,是研究区水稻SPAD值的最佳反演模型。[结论]研究结果可为实现高效、精准的水稻叶片叶绿素含量监测提供参考及依据。 展开更多
关键词 水稻 叶绿素 高光谱 相关系数 主成分分析 extra Tress
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Clinical study on acupuncture for primary insomnia 被引量:8
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作者 Shao Yue 《Journal of Acupuncture and Tuina Science》 CSCD 2017年第6期410-414,共5页
Objective: To observe the clinical effect of Acupuncture at Baihui(GV 20), Sishencong(EX-HN 1) and Anmian [Extra, locates at the midpoint between Yiming(EX-HN 14) and Fengchi(GB 20)] for primary insomnia. Met... Objective: To observe the clinical effect of Acupuncture at Baihui(GV 20), Sishencong(EX-HN 1) and Anmian [Extra, locates at the midpoint between Yiming(EX-HN 14) and Fengchi(GB 20)] for primary insomnia. Methods: A total of 112 patients with primary insomnia were randomized into an acupuncture group and a medication group according to the visiting sequence, 56 cases in each group. The acupuncture group was intervened by acupuncture at Baihui(GV 20), Sishencong(EX-HN 1) and Anmian [Extra, locates at the midpoint between Yiming(EX-HN 14) and Fengchi(GB 20)], and points selected based on syndrome differentiation, while the medication group was by oral intake of zopiclone tablet. The Pittsburgh sleep quality index(PSQI) was measured before and after treatment, and the clinical efficacy was compared after 1 month of treatment. Results: After treatment, subscales of PSQI and global score in the acupuncture group were improved, and intra-group comparisons showed statistical differences(all P〈0.05); subscales of sleep quality, sleep latency, sleep duration and global score of PSQI in the medication group were improved, showing statistical differences(all P〈0.05). Inter-group comparison of global and subscales scores of PSQI showed statistical differences(all P〈0.05). The total effective rate in the acupuncture group was 92.9%, higher than 67.9% in the medication group, and between-group comparison showed a statistical difference(P〈0.05). Conclusion: Acupuncture at Baihui(GV 20), Sishencong(EX-HN 1) and Anmian [Extra, locates at the midpoint between Yiming(EX-HN 14) and Fengchi(GB 20)] as the main treatment method can produce a better effect than oral intake of zopiclone tablet. 展开更多
关键词 Acupuncture Therapy Point Baihui (GV 20) Point Sishencong (EX-HN 1) Point Anmian extra Points Headand Neck Point Selection Based on Syndrome Differentiation INSOMNIA
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Prevalence, diagnosis, and treatment of primary hepatic gastrointestinal stromal tumors 被引量:8
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作者 Xiao-Hui Qian Ying-Cai Yan +1 位作者 Bing-Qiang Gao Wei-Lin Wang 《World Journal of Gastroenterology》 SCIE CAS 2020年第40期6195-6206,共12页
Gastrointestinal stromal tumors(GIST), which is the most common mesenchymal tumor of the digestive tract, account for 1%-3% of gastrointestinal tumors. Primary stromal tumors outside the gastrointestinal tract are col... Gastrointestinal stromal tumors(GIST), which is the most common mesenchymal tumor of the digestive tract, account for 1%-3% of gastrointestinal tumors. Primary stromal tumors outside the gastrointestinal tract are collectively referred to as extra GISTs, and stromal tumors in different regions often have different prognoses. A primary hepatic GIST is a rare tumor with an unknown origin, which may be related to interstitial Cajal-like cells. Although primary hepatic GIST has certain characteristics on imaging, it lacks specific symptoms and signs;thus, the final diagnosis depends on pathological and genetic evidence. This review summarizes all cases of primary hepatic GIST described in the literature and comprehensively analyzes the detailed clinical data of all patients. In terms of treatment, local resection alone or with adjuvant therapy was the prioritized choice to obtain better disease-free survival and longer survival time. For advanced unresectable cases, imatinib mesylate was applied as the first-line chemotherapy agent. Moreover, transcatheter arterial chemoembolization,/by-nc/4.0/Manuscript source: Unsolicited manuscript radiofrequency ablation, and microwave ablation were shown to improve overall survival for selected patients. Liver transplantation was a final treatment option after resistance to chemotherapy developed. 展开更多
关键词 extra gastrointestinal stromal tumor Treatment Liver transplant Review
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Analysis of the Relationship between the Number of Traffic Accidents and the Traffic Flow &Section Location in Extra Long Tunnel 被引量:6
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作者 Zhaoyou Ma Shouen Fang +1 位作者 Shuo Liu Bowen Cai 《Engineering(科研)》 2020年第2期71-81,共11页
In order to study the influence of the traffic characteristics on traffic accidents in extra long tunnel, the main measurement indicators of traffic flow during the time of traffic accidents are matched with the accid... In order to study the influence of the traffic characteristics on traffic accidents in extra long tunnel, the main measurement indicators of traffic flow during the time of traffic accidents are matched with the accident information to form a data set of the number of traffic accidents and the hourly traffic flow of the accident. Vehicle ratio and the number of accidents are mainly used as the characteristic indicators of traffic flow. At the same time, the longitudinal distribution law of the average speed of traffic flow and the number of traffic accidents in the extra long tunnel is studied. Based on the superposition principle, the extra long tunnel is divided into 5 traffic safety zones. This paper analyzes the distribution of time, morphology, cause of accident, and other characteristics in different traffic safety zones, finding that the shape of traffic accidents in extra long tunnel is mainly rear-end collisions. Improper operation and illegal lane changes are the main causes of accidents. 展开更多
关键词 TRAFFIC Safety extra Long TUNNEL TRAFFIC ACCIDENT ACCIDENT ANALYSIS
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Comparative Study of Neurosurgical Complications of Thalassemia and Sickle Cell Disease
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作者 Léon Boukassa Didace Massamba Miabaou +5 位作者 Hugues Brieux Ekouélé Mbaki Sinclair Brice Kinata Bambino Olivier Brice Ngackosso Rel Boukaka Kala Gédéon Colin Thouassa Ruth Ibara Wamé 《Open Journal of Modern Neurosurgery》 2024年第3期190-202,共13页
Introduction: Sickle cell disease and thalassemia are the most frequent hemoglobinopathies. During their evolution, they present certain complications, among which are two neurosurgical emergencies, namely spontaneous... Introduction: Sickle cell disease and thalassemia are the most frequent hemoglobinopathies. During their evolution, they present certain complications, among which are two neurosurgical emergencies, namely spontaneous cranial epidural hematoma and non traumatic radiculo-medullary compression, with some particularities for each. Method: In order to highlight these particularities, we compared the characteristics of these two complications, from a number of publications reported between 2000 and 2021. Results: Sickle cell disease was complicated by spontaneous cranial epidural hematoma. Forty-two cases were reported, the mean age was 14.7 years (2 - 21 years) and the sex ratio was 6.4. The clinical presentation combined, in a non-traumatic context, signs of intracranial hypertension with those of neurological focalization. Neuroimaging showed epidural-type collection, often frontal and parietal in location. The incriminating mechanisms were ischemia, hemorrhage and extra medullary hematopoiesis. The treatment was surgical. Non traumatic radiculo-medullary was the complication of thalassemia. Of the 77 cases reported, the mean age was 27.5 years (9 - 66 years) and the sex ratio was 4.1. The lesions were epidural with a clear thoracic predominance and resulted from extra marrow hematopoiesis. Treatment included: hypertransfusion, radiotherapy, hydroxyurea and surgery. Vital and functional prognosis were globally satisfactory when the management was rapid. Conclusion: Cranial and spinal epidural lesions, respective complications of sickle cell disease and thalassemia, result from similar mechanisms. Their prognosis depends on the rapidity of management. . 展开更多
关键词 HEMOGLOBINOPATHY Sickle Cell Disease THALASSEMIA Spontaneous Epidural Hematoma extra Marrow Hematopoiesis Slow Marrow Compression
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基于Extra Tree Classifier的水质安全建模预测
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作者 杨丽佳 陈新房 +1 位作者 赵晗清 汪世伟 《电脑与电信》 2024年第6期57-61,共5页
随着工业化和城市化的快速发展,水质安全问题日益受到关注。本研究利用一个包含7999条数据记录的水质分析数据集,涵盖多种化学物质浓度测量值与安全阈值,以及“是否安全”分类变量,运用Extr aTree Classifier模型进行水质安全建模预测... 随着工业化和城市化的快速发展,水质安全问题日益受到关注。本研究利用一个包含7999条数据记录的水质分析数据集,涵盖多种化学物质浓度测量值与安全阈值,以及“是否安全”分类变量,运用Extr aTree Classifier模型进行水质安全建模预测及数据分析。本研究目的在于提供一个可靠的模型,以帮助决策者和相关部门更好地监测和维护水质安全,从而保障公众健康和环境可持续发展。 展开更多
关键词 水质安全 Lazy Predict extra Tree Classifier k折交叉验证 机器学习
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From Micropores to Ultra-micropores inside Hard Carbon: Toward Enhanced Capacity in Room-/ Low-Temperature Sodium-Ion Storage 被引量:7
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作者 Jinlin Yang Xiaowei Wang +9 位作者 Wenrui Dai Xu Lian Xinhang Cui Weichao Zhang Kexin Zhang Ming Lin Ruqiang Zou Kian Ping Loh Quan-Hong Yang Wei Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第6期297-310,共14页
Pore structure of hard carbon has a fundamental influence on the electrochemical properties in sodium-ion batteries(SIBs).Ultra-micropores(<0.5 nm)of hard carbon can function as ionic sieves to reduce the diffusion... Pore structure of hard carbon has a fundamental influence on the electrochemical properties in sodium-ion batteries(SIBs).Ultra-micropores(<0.5 nm)of hard carbon can function as ionic sieves to reduce the diffusion of slovated Na+but allow the entrance of naked Na^(+) into the pores,which can reduce the interficial contact between the electrolyte and the inner pores without sacrificing the fast diffusion kinetics.Herein,a molten diffusion-carbonization method is proposed to transform the micropores(>1 nm)inside carbon into ultra-micropores(<0.5 nm).Consequently,the designed carbon anode displays an enhanced capacity of 346 mAh g^(−1) at 30 mA g^(−1) with a high ICE value of~80.6%and most of the capacity(~90%)is below 1 V.Moreover,the high-loading electrode(~19 mg cm^(−2))exhibits a good temperature endurance with a high areal capacity of 6.14 mAh cm^(−2) at 25℃ and 5.32 mAh cm^(−2) at −20℃.Based on the in situ X-ray diffraction and ex situ solid-state nuclear magnetic resonance results,the designed ultra-micropores provide the extra Na+storage sites,which mainly contributes to the enhanced capacity.This proposed strategy shows a good potential for the development of high-performance SIBs. 展开更多
关键词 Carbon anode Ultra-micropores extra sodium-ion storage sites Low-voltage capacity High areal capacity
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Effect of sodium ions in synthesis of titanium silicalite-1 on its catalytic performance for cyclohexanone ammoximation 被引量:5
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作者 Pengxu YAO Yaquan WANG Teng ZHANG Shuhai WANG Xiaoxue WU 《Frontiers of Chemical Science and Engineering》 SCIE EI CAS CSCD 2014年第2期149-155,共7页
Titanium silicalite-1 (TS-1) has been hydrothermally synthesized with tetrapropylammonium hydroxide (TPAOH) as the template in the presence of various amounts of Na+, characterized by inductively coupled plasma, ... Titanium silicalite-1 (TS-1) has been hydrothermally synthesized with tetrapropylammonium hydroxide (TPAOH) as the template in the presence of various amounts of Na+, characterized by inductively coupled plasma, X-ray diffraction, scanning electron microscope, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and ultro-violet-visible spectroscopy and studied in cyclohexanone ammoximation. The characterization results show that with the increase of Na+ concentration in the synthesis, both the crystal sizes of TS- land extra framework Ti increase but framework Ti decreases. The addition of Na+ below 3 mol-% of TPAOH in the synthesis does not influence the catalytic properties with above 98% conversion of cyclohexanone and 99.5% selectivity to cyclohexanone oxime. However, at the concentrations of Na+≥3mol-% of TPAOH in the synthesis, the catalysts are deactivated faster with the increase of Na+ addition, which can be attributed to more high molecular weight byproducts deposited in the large TS-1 particles and the loss of the frame-work titanium. The results of this work are of great importance for the industry. 展开更多
关键词 titanium silicalite-1 sodium ion crystal size extra framework Ti cyclohexanone ammoximation
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Unresolved conundrum of the role of physical activity in inflammatory bowel disease:What next?
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作者 Nilakantan Ananthakrishnan 《World Journal of Gastroenterology》 SCIE CAS 2024年第21期2744-2747,共4页
There is considerable controversy on the role of physical activity in irritable bowel disease(IBD)since published reports are conflicting.It is well known that there is known relapse with specific treatment in IBD.Thi... There is considerable controversy on the role of physical activity in irritable bowel disease(IBD)since published reports are conflicting.It is well known that there is known relapse with specific treatment in IBD.This,in addition to onset of extraintestinal symptoms creates a need to think of alternate approaches.In this context,the current article describes the need of a multi-institutional study with standard protocol of physical activity for documenting its effect on both the primary disease and the extra alimentary manifestations.This paper also points out the possibility of using adjuvant complementary medicine such as yoga,whose effects have been documented in other diseases like irritable bowel syndrome.A third approach could be to focus on the intestinal dysbiosis in IBD and concentrate on research on restoring the microbial flora to normal,to see whether the extraintestinal symptoms are alleviated. 展开更多
关键词 extra intestinal symptoms of inflammatory bowel diseases Management Physical activity in inflammatory bowel diseases Complementary medicine in inflammatory bowel diseases Yoga in inflammatory bowel diseases Dysbiosis in inflammatory bowel diseases
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Rare incidence of mucosa-associated lymphoid tissue lymphoma presenting as buccal fat pad tumor:A case report
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作者 Keitaro Miyake Kazuhiro Hirasawa +1 位作者 Haruka Nishimura Kiyoaki Tsukahara 《World Journal of Clinical Cases》 SCIE 2024年第31期6506-6512,共7页
BACKGROUND Mucosa-associated lymphoid tissue(MALT)lymphoma,a type of non-Hodgkin lymphoma,originates in the mucosal lining of body organs and internal cavities,including the nose,mouth,lungs,and digestive tract.The ly... BACKGROUND Mucosa-associated lymphoid tissue(MALT)lymphoma,a type of non-Hodgkin lymphoma,originates in the mucosal lining of body organs and internal cavities,including the nose,mouth,lungs,and digestive tract.The lymphoma develops when the body produces abnormal B lymphocytes.These lymphomas develop at the edge of the lymphoid tissue,called the marginal zone,and,hence,are classified as a type of marginal zone lymphomas.They are the most common type of marginal zone lymphomas although their occurrence is rare.To date,no previous cases of MALT lymphoma in the buccal fat pad have been reported.CASE SUMMARY We report the case of a patient who presented with a mass on the frontal cheek.Magnetic resonance imaging revealed a tumor in the buccal fat pad,and histopathological and immunohistochemical findings confirmed the diagnosis of MALT lymphoma.The patient had a history of Helicobacter pylori and hepatitis C virus infection,suggesting an association between these infective agents and MALT lymphoma.CONCLUSION Consideration of MALT lymphoma is essential in the differential diagnosis of frontal cheek masses. 展开更多
关键词 Mucosa-associated lymphoid tissue lymphoma extra gastric mucosaassociated lymphoid tissue lymphoma Plain computed tomography Helicobacter pylori Case report
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